The answer should be C, It diffuses from the alveoli into the blood.
Alveoli, also called the air sac, is the place where the oxygen we breathed in is exchanged with carbon dioxide that our body produces. Oxygen is passed into the blood in the capillaries through the process of diffusion, while carbon dioxide is diffused from the blood back to the alveoli, so that we can exhale the carbon dioxide after that.
Both a and b are not right because when we breathe in, the oxygen travels from the trachea to the bronchi, to the bronchiole, and to the alveoli, instead of directly into blood vessels like arteries, capillaries, or veins. d is also not right because the direction is wrong.
Therefore, your answer should be C.
<span> it goes back to the root of the words:
auto means self---------------trophic refers to feeding--so an autotroph is a self feeding organism
hetero---refers to different-------so then a heterotrophe feeds on some thing different
A...
Hope this helps ! :)
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<span>In any population of bears, some individuals have thick fur, some have thin fur, and some are in between. As temperatures increase with the passage of time, the survival of bears with thin fur will increase, and the number of bears in the population with thick fur will decrease.</span>